story to find out more.
Chemist Betty Burri
loads homogenized freeze-dried pumpkin samples into a supercritical fluid
extractor for carotenoid analysis. Click the images for more information
Pumpkin's Tantalizing Carotenoids
Scrutinized By Marcia Wood October 11, 2005
Cans of cooked, pureed pumpkin on the pantry shelf, ready to make into
a rich, creamy pumpkin pie or a hearty soup, probably have more beta-carotene
than any other food in the cupboard. Our bodies can convert this healthful
carotenoid and antioxidant into vitamin A, a nutrient essential for good
eyesight and proper growth.
Until now, there hasnt been a fast, simple and environmentally
friendly way to precisely measure the beta-carotene and other carotenoids in
pumpkin. Studies led by Agricultural
Research Service chemist
Burri help fill that technology gap by showing that a process known as
supercritical fluid extraction, or SFE, efficiently draws out significant
amounts of carotenoids from pumpkin samples.
Also, pairing SFE with another technology--reversed-phase liquid
chromatography--to identify and measure the extracted compounds is less-labor
intensive than some other options; doesn't require harsh chemicals; and
provides rapid, reliable, reproducible results.
Nutrition and public health researchers worldwide want to learn more
about beta-carotene and other carotenoids, the natural plant compounds
responsible for the orange hues of pumpkins and carrots and the deep reds of
tomatoes. That's because some carotenoids are thought to help reduce incidence
of cataracts, cardiovascular disease and particular kinds of cancer.
Beta-carotene is still the most-studied carotenoid. But the importance
of other carotenoids, such as cryptoxanthin, lutein and lycopene--and the
amounts in which they occur--isn't well known, according to Burri. She's based
at the ARS
Human Nutrition Research Center in Davis, Calif.
Neither SFE nor reversed-phase chromatography is new. But Burri and
colleagues are apparently the first to provide detailed guidelines for using
these techniques to more precisely measure carotenoids in pumpkin and other
squashes. Their work, which they reported in the
Chromatography earlier this year, is highlighted in
article in the October issue of Agricultural Research magazine.
ARS is the U.S. Department of
Agriculture's chief scientific research agency.